This AutoLISP-based 3D Ductwork Program for AutoCAD demonstrates true object-oriented design within CAD automation. It allows engineers to model HVAC duct systems — including transitions, endcaps, and boots — while embedding complete geometric and engineering data within each object.
About This Project
Developed as a proof of concept for an HVAC engineering firm in Costa Rica, this program extends traditional 2D duct automation into a fully interactive 3D environment. Each duct element stores all of its geometry, dimensions, and fabrication data directly inside the drawing’s object structure, allowing for intelligent modification, redrawing, and downstream analysis.
The result is a dynamic 3D duct modeling tool capable of:
- Automatic generation of 3D duct runs, transitions, boots, and endcaps
- Embedded geometric and material data for every object
- Instant redrawing and regeneration after parameter changes
- Data export directly to duct fabrication machinery
- Streamlined communication between design and production teams
By combining object-oriented AutoLISP programming with precise 3D modeling, this project demonstrates how advanced CAD automation can bridge design and manufacturing, reducing rework and accelerating production.
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